SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f11465b46810dec33abcde208a5cb20daa08a78d3fe1f3c048657d94e74ce1d' 
  AND token = 'Z3Et+Ta0NHz2GEZjTwzgSD4jCZgf696aAeKacqVeKzw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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