SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a11643f4ad4e3f709d654179b30019886ecca74b380922b3c1a7a0e15fca742' 
  AND token = 'qpz1JBSVLokveYKnLiaPvMwf3C3ZprtG5dsQXv01X+8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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