SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b18685c9ca1d72408b5aa1e4ed0a1f518028e24626309f5ebf7fa460ecb58df6' 
  AND token = 'DS484ReeD1bDLuMARNFYQnEACOJBC4/FrOGlgfObJKM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}